Illustrations of Indian Botany, Vol. 1/Sapindaceae

by Robert Wight

XXXVII.—SAPINDACEAE.

This is a large and complex order presenting among its members slender climbing herbs, small shrubs, and large umbrageous trees. The leaves are alternate, simple, or compound; in the latter case, either ternate, or biternate, more frequently abruptly pinnate. The flowers equally vary, being either uni or bi-sexual, or frequently presenting both forms on the same tree, polygamous. The inflorescence is either racemose or panicled, the flowers usually small, sometimes nearly inconspicuous, generally white, or pale greenish white, more rarely purplish coloured.

Calyx free of 4-5 distinct or slightly cohering sepals, imbricated in aestivation. Petals usually as many as the sepals, alternating with them, sometimes fewer by the abortion of one, or altogether wanting, either naked, hairy, glandular, or furnished with a petaloid scale within, and also imbricated in aestivation. Torus usually a hypogynous disk, occupying the bottom of the calyx, expanded between the petals and stamens. Stamens 8-10 in a single series, inserted on the disk or receptacle between the glands and ovary; filaments free, anthers incumbent, 2-celled, bursting longitudinally, introrse, when polygamous, the pistil of the male flower is either rudimentary, or wanting. In the female the ovary is usually 3, rarely 2, or 4-celled, usually with a single erect or ascending ovule in each, rarely with two superposed ovules, and then one is ascending, the other pendulous; sometimes they are numerous. Style undivided or 3-cleft, more rarely, bifid. Fruit fleshy and indehiscent, or vesicular, or capsular, and 2-3 valved, some of the cells occasionally abortive. Seeds usually arillate, albumen none. Embryo usually curved, or spirally convolute, rarely straight; radicle pointing towards the hilum. Cotyledons sometimes conferruminate.

Affinities. The relationship of this with the three preceding orders will be evident from a reference to the Conspectus, page 137, where it is introduced as a member of the class Malpighinae, other affinities are indicated by Botanical writers, but as these appear somewhat remote I shall not myself attempt to detail them, but rather extract from Dr. Lindley's Natural System of Botany the paragraph in which they are explained.

"From Aceraceae these scarcely differ, except in their alternate leaves and petals, which have almost always an appendage on their surface. In some respects near Meliaceae, which agree in habit and in their pinnated leaves, but which are known by their monadelphous stamens and symmetrical flowers. To Polygalaceae they are no doubt akin in the singular combination of 8 stamens with 5 unequal sepals, and an uncertain number of petals; and also in their aril, which may be compared to the caruncula of Polygalaceae, although somewhat different in its origin. The dried leaves resemble, as DeCandolle remarks, those of Connaraceae. Their climbing habit and tendency to produce tendrils indicate a relation to Vitaceae, which, however, is not very near. Brown remarks, that although in the far greater part of this family the ovule is erect, and the radicle of the embryo inferior, yet it includes more than one genus, in which both the seeds and embryo are inverted."

To me it is matter of surprise that there is no allusion in any work I have had an opportunity of consulting to any affinity existing between this order and Euphorbiaceae, though some of the genera of each order seem so closely allied that it is difficult to say to which order they ought to be referred.

Geographical Distribution. This large order is nearly confined to the tropics, or extends but a short way beyond, being still limited to the warmer latitudes on either side. The greater number of species are natives of Equinoctial America, and India; Africa also has many of them, but they are unknown as natives in Europe and the United States of America, while the genus Dodonaea alone represents them in New Holland. We have not the same data for estimating the number of Indian species as in most of the other orders yet gone through, as they are not included in Wallich's list of Indian plants. The number of Peninsular ones known to us amounted however to only 14, and these have not since been augmented. This I should suppose falls greatly short of the actual number as Blume in his Bijdr : Florae Java?, has no fewer than 23 species, and in Ceylon there are several that have not yet been met with on the continent, though it seems to me they are such as might be expected. Those met with on the continent occupy very different stations. Thus Cardiospermum Halicacabum is commonly met with in hedges and corn fields, while C. canescens is rarely met with except in dry jungles, where it appears as a very extensive climber, and when in full flower, which it is the greater part of the year, is really a pretty plant. The Sapindus emarginatus is generally met with as a cultivated plant, but is not rare in subalpine jungles in a wild state. The same remark applies to Schleichera trijuga. Nephelium Longanum on the other hand, a species very closely associated with Litchi, I have only seen in jungles, and usually at a considerable elevation. The Schmidelias which are shrubby very ramous plants, sometimes becoming small trees, and bear a small red berry, are always so far as I have seen, jungle plants. Our only species of Cupania, C. canescens, is never I believe met with in cultivation, but is a common plant in subalpine jungles and has a wide distribution over India.

Properties and Uses. This family is remarkable on account of the leaves and bark, and even the fruit of some of its species being possessed of active medicinal or even decidedly poisonous properties, while the fruit of others, is highly esteemed for the dessert. Among these last are the Litchi, the Rambutan, the Longan, and a variety of others. The root of Cardiospermvm Halicacabum is aperient. The succulent capsule of Sapendus emarginatus, the common Soapnut, is considered by the native practitioners an excellent expectorant, an opinion which Dr. Ainslie thinks correct, it is also, as the English name implies, a useful detergent, and much used as such. The root Schmidelia serrata (Ornithrophe Roxb.) is according to Roxburgh a mild astringent, and prescribed by the natives in cases of diarrhasa, while the small red subacid berries are eaten by the natives. So also is the subacid aril of the seed of Schleichera trijuga, a large and handsome tree, not uncommon in our jungles; and from the seed themselves a lamp oil is expressed in Malabar.

Remarks on Genera and Species. The discrimination of the genera of this order is often most difficult, unless the specimens under examination are very complete. When furnished with both flowers and fruit the characters are more easily made out, but without fruit the reverse is often the case, as for example, between some of the species of Cupania and Sapindus. With these exceptions the Sapindaceae of the Indian Peninsula are for the most

part easily distinguished—Cardrospermum has bladdery 3-celled capsules and climbs by tendrils. Schmidelia has soft pulpy berries, 3 foliolate leaves, and a shrubby ramous habit. Nephelium at least the Peninsular species is known at first sight by its rough tuberculated fruit, which is usually only 1-celled. Schleichera by the want of petals and by its globose 1-seeded fruit being pointed with the persistent base of the style, and not unfrequently armed all over with projecting prickles. Sapindus is distinguished by its lobed fruit, each lobe 1-seeded, the seed not furnished with an ariilus, while in Cupania the fruit is 3 angular 3-celled, each cell with a single seed furnished with an ariilus. When in flower only it is difficult to distinguish the two last. Dodonaea is at once known from all its Indian allies by its winged carpels.

With respect to species 1 have but little to add, except that in many instances they are apt to vary exceedingly and become of difficult determination, hence in some genera, there is reason to believe, they have been unnecessarily multiplied. No new Peninsular ones have been added to my collection with the exception of Sapindus laurifolius, of which I have now Peninsular specimens. Our Sapindus deficiens, of the genus of which owing to our specimens wanting fruit, we were doubtful, i have now ascertained to be really a Sapindus, and also that it is a native of Ceylon as well as of the continent. It appears very nearly allied to S. rubiginosus, like it two of its cells often aborting from an early stage. It is truly a superb species, its racemes sometimes attaining nearly two feet in length, and the leaflets of the leaves from 12 to 15 inches. The flowers are, so far as I have seen, the largest of the genus. These more perfect specimens have shown that a correction in the character of this species is required, the petals in place of being "oblong attenuated into the unquis woolly at the back and lower half of the margin" I find to be nearly orbicular and glabrous. In all other respects our character agrees well with the specimens. Sapindus squamosus Roxb. seems to exist in Ceylon, I have a specimen from that country so nearly answering to his description as scarcely in my mind to leave a doubt of its being that plant. S. microcarpus (W. and A.) I have now ascertained does not belong to the genus, but is a Millingtonia which I have figured under the name of M. Arnottiana. Ceylon presents an undescribed species of Nephelium, named by Mr. Moon in his catalogue Democarpus pupilla, (N. pupillum) the fruit of which is oblong ovare, attenuated towards the apex and perfectly smooth, without warts or tubercles, in other respects it is so nearly allied to N. Longanum that actual comparison is required for their discrimination, when some slight differences become obvious, but not sufficient to distinguish them by written characters. Of Schleichera I have now specimens with smooth unarmed fruit, but which, so far as I can perceive, do not otherwise differ from S. trijaga, on which account I am disposed to consider the two forms varieties only.

The species of Schmidelia are all so nearly allied and so variable in their forms that I can scarcely help thinking that there are not more than a very few appertaining to the genus, though Roxburgh describes 7 Indian ones, including Aporetica pinnata of authors, but excluding S. Allophyllus, a Ceylon plant, which DeCandolle includes — DeCandolle, exclusive of Aporetica which he retains as a distinct genus, has 18 species, but I fear not all good. The two described in the Peninsular Flora, are perhaps, nothing more than varieties. The only mark by which I have been able to distinguish them is to be found in the inflorescence, being in S. serrata a simple undivided spicate raceme, while in S. Cobbe it is branched, but this is not a good distinction, since I have seen unbranched spikes mixed on the same plant with branched ones.

The species of Dodonaea like those of Schmidelia are difficult to discriminate, and have I suspect been needlessly multiplied, owing to imperfection of materials; mere variations, of specimens having in many instances been elevated to the rank of species. In India I have certainly never seen more than one species, though I have them from all quarters—and from every grade of ascent from the level of the sea to an elevation of 7000 feet on the Pulney mountains, where the plant figured in plate 52 was obtained. Among the specimens collected there, variations occur sufficient, if procured under other circumstances, to form two or three species, but which are certainly all referable to one.

EXPLANATION OF PLATE 51.

1. Sapendus emarginatus, natural size.

2. A full grown flower.

3. The same, the sepals thrown back to show the insertion of the petals.

4. Sepals and petals removed, to show the insertion of the stamens in a bisexual flower.

5. Stamens back and front views,

6. A female flower dissected.

7. The ovary cut transversely, 3-celled.

8. The same cut vertically, ovules erect.

9. A small but mature fruit, natural size.

10. The same cut transversely.

11. A portion of a leaf magnified to show the pubescence—with the exceptions mentioned, all more or less magnified.

EXPLANATION OF PLATE 52.

1. Dodonaea Burmanniana, (D. C.) natural size.

2. A bisexual flower, but with the male organization highly developed.

3. Stamens removed to show the ovary.

4. The ovary cut transversely.

5. The same cut vertically, showing in this instance solitary ovules.

6. A bisexual flower, the female organization predominating.

7. Stamens.

8. The ovary cut transversely.

9. Cut vertically, showing the ovules double and superposed, the one ascending the descending.

10. Detached ovules, showing their large curunculoid funeculus.

11. A different view of the same.

12. A mature fruit showing its winged carpels, natural size.

13. The same cut transversely, natural size.

14. A mature seed—with the exceptions mentioned, all more or less magnified.

SAPINDACEÆ

SAPINDUS EMARGINATUS.